mozabt



Urrnn SrA'rns FFICE.

.Partnr DON J. MOZART, OF NEV YORK, N. Y.

Spcciiication forming part 0l" Letters Patent No. 121,401, dated November 2S, 1871.

Tov all whom it may concern.-

Be it known that I, DON J. MOZART, ot the city, coinity, and State of New York, haveinvented a new and useful Improvement in Wvatches, and I do hereby declare that the following is a full, clear, and exact description thereof, which will enable others skilled in the art to make and use the same, reference being had to the accompanying drawing' forming part of this specification.

My invention consists in the improvement of watch escapements, as hereinafter fully described and subsequently pointed out in the claims.

In the accompanying' drawing, Figures 1, 2, and 3 represent detail horizontal sectional views on an enlarged scale, of my improved escapement, showing it in dill'erent positions. Fig. et is a detail side view ol" the notched part ot' the balance-wheel statt. Figs. 5 and o' are detail horizontal sectional views ot a modilied arrangement olAl the escapement, showing it also in dil'- ferent positions. Fig. 7 is a general side view of the escapement.

Similar letters ol' reference indicate corresponding parts.

l will lirst proceed to describe the esca-pement mechanism, which is composed ot the escapement-wheel A, balance-wheel 15, stall O, and ol' the detent-arbor D, which constitutes also the arbor l'or the second-hand a.. The escapementwheel bears with its teeth against a llattened or two-toothed part of the arbor l), and imparts thereby the necessary rotary motion to said arbor. The llattened part or' the arbor D forms two teeth or prongs, b and c, Awhich are separated by concave portions d and e, as is clearly shown in Figs. l, 2, and 3. The said prongs are ol' such size and so shaped that, when a tooth ot' the esca-pement-wheel bears against the end ol' one-say b it will have leverage enough on it to impart a quarter revolution to the arbor, moving it trom the position shown in Fig. 2 to that shown in Fig. 3. The impelling tooth otr-X now enters with its point the cavity e, which is also so curved as to provide leverage for another quarter turn ol' the arbor D, at the end of which the end oil the next prong, c, comes under the inlluence oi' the nent tooth ot' the escapement-wheel, which continues the operation. In this manner a double mechanism l'or controlling the movements of the hair-sprin g statt' is provided, one being the escapement-wheel direct and the other the arbor D.

Before explaining how I utilize this double mechanism, l desire to point out the detects ot1 ordinary escapements springing l'rom the back oljust such adouble regulator. rlhe ordinary escapement has a projecting pin or ruby on the stall', which receives an impulse from the doublepronged anchor alternately in opposite directions. The impulse l'or either movement is given when the ruby-pin is in onethe central position, and exerts its intluence to the very end ol' its extent-or, in other words, until the power ol' the hair-springexceeds that of the impulse. The hair-spring will then, in attempting to adjust itself, carry the stall' back until the ruby-pin is again in the central position, where it receives an impulse in the opposite direction, and so forth, every stroke using the entire torce ol" the inipulse as against that ot' the hair-spring. This arrangement, although satisfactory in a limited degree, is nevertheless unreliable as to exactness, since too much reliance is placed upon the slender hair-spring, whose slight power varies under the least change ol temperature and atmosphere. The division ot' the movements otl the second-hand, which is more than any other part of the watch, dependent upon the exactitude ol' escapement, becomes dillicult bythe use ol'the old mechanism, and has, whenever ell'ected, added greatly to the complication and expense ol' the watch.

By my double-regulating and impellingmeclianism l am enabled to give the impulse at the end of each swing ot the lmlance-wheel, and not to the middle, as betere, and thereby to conline the vibrations ol" the balance-wheel between certain delinite limits. A beautiful precision is thus produced by simple means, and the subdivision ol' the second movement made easy by the merc application ot' detent-arms to th 1 arbor D.

The statiIl O carries a projecting lever,j`, anda notched shoulder, y, which at one end, lz., terms a surface for contact with the teeth of the escapement-wheel. rEhe arbor l) carries two projecting arms, i I1', in the ends ot' which pins] and k, called impelling ruby-pins, are respectively set. The arbor D has also tour radial arms or detents, l, m, la, and o, so set that the arms Ii 'i are respectively between the arms i m and o ln, as is clearly shown in Figs. 1, 2, and 3 oli' the drawing. The ends of the diametrically-opposite detents and o are bent up or down to be in a higher or lower plane from that in which the ends of the remaining detents move. The distance between the staff C and the arbor D and the length ot' the detents are such that the ends of the latter will reach the staff and be in contact with it until certain notches, p and r, cut into the sides of the staff, come inline with the ends of the detents to let them pass. As the ends of the detents are in different planes, as aforesaid, the notches p and r are at different heights, as shown in Fig. 4, and the notches are also cut in different angles, as the staff is in different positions as it lets the several detents pass.

The escapement operates as follows: When the esoapement-wheel strikes with one tooth the face h of the shoulder g, the parts will be in-position shown in Fig. 2, the balance-wheel swinging still slightly under the impulse given by the escapcment-wheel, in the direction of the arrow l, Fig. 2. The impulse ceasing, the balance returns and brings the notch r in line with the detent m, which had been resting against the staff. The hair-spring, in thus reversil'lg the motion of the stad, as indicated by the arrow l in Fig. l, will cause the contact of the escapement-wheel with the staff to cease, as the tooth cleared the face h. But the contact of the escapement-wheel with the arbor D never ceases, as above described, so that said arbor has a constant tendency to turn in the direction of the arrow 2, shown in Figs. l, 2, and 3. After, therefore, the detent m has been released, the arbor D is turned so a-s to carry the ruby-pin j against the concave edge of the lever f, said ruby-pin following.;` on the lever, while the same completes its movement in the direction of the arrow 1X. Fig. I shows the parts during this movement, and must not be misunderstood for a position at rest, being merely the middle movement between the stoppage produced by the detents m and Z. The ruby-pin j, by being in contact with the lever f, gives the impulse to the balance-wheel in the direction 1X, which impulse was started by the hair-spring, as aforesaid. As soon as the ruby-pin j has rolled past the lever j', the detent l strikes the staff and arrests the further motion of the arbor, (see Fig. 3,) until by the return movement of the staff, started by the hair-spring, the notch p is brought opposite the said detent to let the same clear it. The staff now moves again in the direction of the arrow l, and during this motion the next tooth of the escapement-wheel strikes the face h., and gives the second impulse to the balancewheel, until the parts are again in position, shown in Fig. 2, except that the detent o will be in contact with the staff. Thus the necessary impulse is given in opposite directions at the commencement of each vibration of the staff, and not, as heretofore, only after the balance has righted'itself. As the second-hand is directly affixed to the arbor D, and as the latter makes one revolution during every second, the

detents, whenever they rest against the staff, will arrest the movements of the second-hand to produce the desired quarter-second divisions.

By omitting reference to the detents, the movement of the escapement may be summed up in the sta-tement that the staff receives an alternate impulse by escapement-wheel and ruby-pin, and that immediately after each impulse has spent itself, the hair spring will reverse the movement of the staff, bringing it directly under the influence of the opposite impulse. The detents strike the arbor at the ends of each vibration, and slip by it at the commencement of rthe next vibration.

Instead of using four detents I may have but two, as shown in Figs. 5 and 6, by using in place of the leyer j' a notched disk, s, which will arrest the ruby-pins until the notch comes in line with them, causing thereby the said ruby-pins to constitute detents as well as impellers. The shoulder g is the same as above described, and has also the face h to receive the impulse by the escapement-wheel. The pins j k are set to arms t', and detents l and n project from the arbor, as is clearly shown in Figs. 5 and 6.

Although this modilication is still simpler and cheaper than the first-described escapcment, and embodies the same principles of operation, I consider the irst moreeXact and desirable, as, among other advantages, it produces less friction, and gives greater play to the mainspring.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. The arbor D, having the prongs b c and intervening cavities d c, to be moved by constant contact with the escapement-wheel, and aid in impelling the staff, as set forth.

2. The staff C provided with recessed faces r p engaging with revolving detent arms, and the shoulder g having end surface h, combined with the escapement-wheel A, as and for the purpose set forth.

3. The revolving arms of arbor D having ruby-pins j 7c on the ends thereof, combined, as described, with projection j' of the staff C, for the purpose set forth.

4. The detent arms aiixed to the arbor D, which carries the second-hand to abut against the staff and produce quarter-seconds, as set forth.

5. An escapement, composed of the wheel A, pronged arbor D, which carries the ruby-pins j 7c, and the detents, and ofthe staff G, having the stops f and g, as set forth, all operating as spec- 6. The staff C, having notches, p r, of different heights and angles, combined with two pairs of revolving radial arms of the arbor D, as and for the purpose described.

DON J. MOZART.

Witnesses GEO. W. MABEE, ALEX. F. ROBERTS. (36) 

